Class 10 CBSE Science NCERT solution Q. Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans ? ANS. In multi-cellular organisms like humans, the body structure is very complex as well as they need a proper supply of oxygen to each and every cell for cellular processes within a very few time . Unlike the unicellular organisms , multi-cellular organisms do not have all their cells directly in contact with the atmosphere for diffusion to occur. Therefore, it is insufficient to meet the oxygen requirements of multi-cellular organisms by the process of diffusion.
LAW OF CONSERVATION OF MASS This law was put forth by Antoine Lavoisier in 1789. He performed careful experimental studies for combustion reactions and reached to the conclusion that in all physical and chemical changes, there is no net change in mass during the process. Hence, he reached to the conclusion that matter can neither be created nor destroyed. This is called ‘Law of Conservation of Mass’ . This law formed the basis for several later developments in chemistry. In fact, this was the result of exact measurement of masses of reactants and products, and carefully planned experiments performed by Lavoisier. This is one of the five basic Laws Of Chemical Combinations. ANTOINE LAVOISIER Father Of Chemistry